uni-app实现微信APP支付的全过程详解（附赠全部代码）
背景
最近项目使用uni-app实现微信支付，把过程简单记录下，帮助那些刚刚基础uni-app，苦于文档的同学们。
整体来说实现过程和非uni-app的实现方式没有太大不同，难点就在于uni-app对于orderInfo的格式没有说明。
准备工作
- 申请了商户号，拿到了API秘钥。这个需要微信开发平台，相关的工作大家百度。
- 后面代码里用到的appid和秘钥之类需要实现申请号。
- 在uni-app manifest.json 配置sdk支付权限
前端代码
- onload阶段获取了可用支付列表，这里我们只用到了微信支付。
- requestPayment
a. getOrderInfo 获取到订单信息，主要是prepayid，对应统一下单api的返回值。
b. uni.requestPayment发起支付，效果就是弹出微信支付框输入密码支付。第一个参数是“wxpay”，第二个参数就是OrderInfo.
前端代码很简单，重点是如何让后端返回OrderInfo以及OrderInfo的格式。
支付金额
￥
后端代码（springboot）
核心代码
import com.alibaba.fastjson.JSONObject;
import com.bian.common.core.domain.AjaxResult;
import com.bian.common.utils.StringUtils;
import com.bian.framework.config.jwt.AuthService;
import com.bian.sales.entity.Constant;
import com.bian.sales.entity.PayInfo;
import com.bian.sales.service.IWxService;
import com.bian.sales.util.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;
import com.thoughtworks.xstream.XStream;
import org.springframework.http.HttpEntity;
import org.slf4j.Logger;
import javax.servlet.http.HttpServletRequest;
import java.util.*;
@Service
public class WxServiceImpl implements IWxService
{
Logger logger = LoggerFactory.getLogger(WxServiceImpl.class);
@Override
public AjaxResult goWeChatPay(String brokerId, HttpServletRequest request) throws Exception {
String clientIP = CommonUtil.getClientIp(request);
logger.error("openId: " + brokerId + ", clientIP: " + clientIP);
String randomNonceStr = RandomUtils.generateMixString(32);
Map result = unifiedOrder(brokerId, clientIP, randomNonceStr);
System.out.println(request.toString());
if(StringUtils.isBlank(result.get("prepay_id"))) {
return AjaxResult.error("支付错误");
} else {
logger.info("支付成功");
Map jsonObject = new LinkedHashMap();
String noncestr = RandomUtils.generateMixString(32);
String prepayid = result.get("prepay_id");
String timestamp = String.valueOf(new Date().getTime()/1000);
jsonObject.put("appid",Constant.APP_ID);
jsonObject.put("noncestr",noncestr);
jsonObject.put("package","Sign=WXPay");
jsonObject.put("partnerid",Constant.MCH_ID);
jsonObject.put("prepayid",result.get("prepay_id"));
jsonObject.put("timestamp",new Date().getTime()/1000);
jsonObject.put("sign",getSignforPayment(noncestr,prepayid,timestamp ));
return AjaxResult.success(jsonObject);
}
}
/**
* @Function: 去支付
* @author: YangXueFeng
* @Date: 2019/6/14 16:50
*/
/**
* 调用统一下单接口
* @param brokerId
*/
private Map
(String brokerId, String clientIP, String randomNonceStr) {
try {
//生成预支付交易单，返回正确的预支付交易会话标识后再在APP里面调起支付
String url = Constant.URL_UNIFIED_ORDER;
PayInfo payInfo = createPayInfo(brokerId, clientIP, randomNonceStr);
String md5 = getSign(payInfo);
payInfo.setSign(md5);
logger.error("md5 value: " + md5);
String xml = CommonUtil.payInfoToXML(payInfo);
xml = xml.replace("__", "_").replace("", "1");
//xml = xml.replace("__", "_").replace("", "");
logger.error(xml);
StringBuffer buffer = HttpUtil.httpsRequest(url, "POST", xml);
logger.error("unifiedOrder request return body: \n" + buffer.toString());
Map result = CommonUtil.parseXml(buffer.toString());
String return_code = result.get("return_code");
if(StringUtils.isNotBlank(return_code) && return_code.equals("SUCCESS")) {
String return_msg = result.get("return_msg");
if(StringUtils.isNotBlank(return_msg) && !return_msg.equals("OK")) {
logger.error("统一下单错误！");
return null;
}
String prepay_Id = result.get("prepay_id");
return result;
} else {
return null;
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 生成统一下单接口的请求参数
* https://pay.weixin.qq.com/wiki/doc/api/app/app.php?chapter=9_1
* @param brokerId
* @param clientIP
* @param randomNonceStr
* @return
*/
private PayInfo createPayInfo(String brokerId, String clientIP, String randomNonceStr) {
clientIP ="222.72.148.34";
Date date = new Date();
String timeStart = TimeUtils.getFormatTime(date, Constant.TIME_FORMAT);
String timeExpire = TimeUtils.getFormatTime(TimeUtils.addDay(date, Constant.TIME_EXPIRE), Constant.TIME_FORMAT);
String randomOrderId = CommonUtil.getRandomOrderId(); //生成随机商品订单号
PayInfo payInfo = new PayInfo();
payInfo.setAppid(Constant.APP_ID);
payInfo.setMch_id(Constant.MCH_ID);
payInfo.setDevice_info("WEB");
payInfo.setNonce_str(randomNonceStr);
payInfo.setSign_type("MD5"); //默认即为MD5
payInfo.setBody("必安glJSAPI支付测试");
payInfo.setAttach("支付测试4luluteam");
payInfo.setOut_trade_no(randomOrderId);
payInfo.setTotal_fee(1);
payInfo.setSpbill_create_ip(clientIP);
payInfo.setTime_start(timeStart);
payInfo.setTime_expire(timeExpire);
payInfo.setNotify_url(Constant.URL_NOTIFY);
payInfo.setTrade_type("APP");
payInfo.setLimit_pay("no_credit");
// payInfo.setOpenid(brokerId);
return payInfo;
}
private String getSign(PayInfo payInfo) throws Exception {
StringBuffer sb = new StringBuffer();
sb.append("appid=" + payInfo.getAppid())
.append("&attach=" + payInfo.getAttach())
.append("&body=" + payInfo.getBody())
.append("&device_info=" + payInfo.getDevice_info())
.append("&limit_pay=" + payInfo.getLimit_pay())
.append("&mch_id=" + payInfo.getMch_id())
.append("&nonce_str=" + payInfo.getNonce_str())
.append("¬ify_url=" + payInfo.getNotify_url())
// .append("&openid=" + payInfo.getOpenid())
.append("&out_trade_no=" + payInfo.getOut_trade_no())
.append("&sign_type=" + payInfo.getSign_type())
.append("&spbill_create_ip=" + payInfo.getSpbill_create_ip())
.append("&time_expire=" + payInfo.getTime_expire())
.append("&time_start=" + payInfo.getTime_start())
.append("&total_fee=" + payInfo.getTotal_fee())
.append("&trade_type=" + payInfo.getTrade_type())
.append("&key=" + Constant.API_KEY);
System.out.println("排序后的拼接参数：" + sb.toString());
return CommonUtil.getMD5(sb.toString().trim()).toUpperCase();
}
private String getSignforPayment(String noncestr,String prepayid,String timestamp) throws Exception {
StringBuffer sb = new StringBuffer();
sb.append("appid=" +Constant.APP_ID)
.append("&noncestr=" + noncestr)
.append("&package=" + "Sign=WXPay")
.append("&partnerid=" + Constant.MCH_ID)
.append("&prepayid=" + prepayid)
.append("×tamp=" + timestamp)
.append("&key=" + Constant.API_KEY);
System.out.println("排序后的拼接参数：" + sb.toString());
return CommonUtil.getMD5(sb.toString().trim()).toUpperCase();
}
}
代码说明
以上代码goWeChatPay从controller层跳转并返回结果给controller接口。所有过程参考微信官方文档的2个接口
- 统一下单接口后端
- 调起支付接口前端已实现
unifiedOrder对应了统一下单接口，看起来很复杂，其实就做了一件事就是拼接参数。拼接参数时涉及到了签名算法，理解这个算法是关键，建议花时间理解透彻这个算法。
createPayInfo，创建一个PayInfo的类，对应了提交的各个参数。
getSign，签名算法的具体实现，获得提交参数的sign。
以上完成了统一下单接口的过程，如果return_code返回“SUCCESS”,result_code返回OK，我们会获得prepay_id（预支付交易会话标识），到这里已经完成了后端内容。但为了使用uni-app我们需要按照如下格式返回给前端,
{"data": {
"appid": "wx0411fa6a39d61297",
"noncestr": "5JigiIJicbq8hQI2",
"package": "Sign=WXPay",
"partnerid": "1230636401",
"prepayid": "wx21204902147233e222e12d451613768000",
"timestamp": 1571662142,
"sign": "0E5C9B9B1C8D7497A234CCC3C721AB1F"
},
"statusCode": 200,
"header": {
"Content-Type": "text/plain;charset=UTF-8",
"X-Android-Response-Source": "NETWORK 200",
"Date": "Mon, 21 Oct 2019 12:49:02 GMT",
"EagleId": "74cf71a315716621419605339e",
"Vary": "[Accept-Encoding, Accept-Encoding]",
"X-Android-Received-Millis": "1571662145735",
"Timing-Allow-Origin": "*",
"_": "HTTP/1.1 200 OK",
"X-Android-Selected-Protocol": "http/1.1",
"Connection": "keep-alive",
"Via": "cache28.l2et15-1[208,0], kunlun5.cn1241[504,0]",
"X-Android-Sent-Millis": "1571662145071",
"Access-Control-Allow-Origin": "*",
"Server": "Tengine",
"Transfer-Encoding": "chunked"
},
"errMsg": "request:ok"
}
重点是data部分，就是uni-app要求的OrderInfo的格式，getSignforPayment就是该部分的签名算法。
以上如果实行正确，应该就可以正常发起微信支付。
参考文档
https://uniapp.dcloud.io/api/plugins/payment?id=requestpayment